The invention relates to a method for producing a coupling compound and to a cross-coupling catalyst. Coupling compounds are useful as pharmaceuticals, agricultural chemicals, liquid crystal materials, organic EL materials, or synthetic intermediates thereof.
There are disclosed Suzuki cross-coupling reactions between aryl halide compounds and aryl boron compounds catalyzed by palladium phosphine complexes and also a coupling reaction between aryl halide compounds and aryl boron compounds catalyzed by nickel phosphine compounds or a nickel catalyst containing nickel compounds and triethylamine or bipyridyl (e.g. Tetrahedron 55(1999) 11889-11894).
It is also disclosed (for example, Angew. Chem. Int. Ed., pp. 3910-3912, 2002) that cross-coupling of alkyl halides can be only achieved by using the expensive palladium phosphine complex compound but they are less reactive than aryl halides.